1. Field of the Invention
The present invention relates to a cleaning system and method for use in clean-in-place (CIP) operations, such as, e.g., dairy processing facilities. More particularly, the present invention relates to a system and method involving a two-part cleaning composition concentrate, in which a first concentrated solution comprises an alkaline material, and a second concentrated solution comprises an enzyme.
2. Prior Art
Many commercial products are available today for use in clean-in-place industrial applications such as, e.g., dairy processing facilities, beverage processing facilities, or breweries. Traditional alkaline cleaner use solutions generally include chlorine and a highly alkaline material and normally have an approximate pH of 12.
Many of the conventional cleaning products available today, for use in clean-in-place applications, include chlorine. Some concerns have arisen, regarding the use of chlorine, for environmental reasons. For example, the chlorine may combine with organic compounds to create chlorinated organic compounds which may pose long term health risks. Accordingly, there is a need for effective cleaning compositions for use in clean-in-place systems, which do not require the inclusion of chlorine.
Heretofore, the use of alkaline proteases in cleaning compositions has been proposed in the prior art, and a summary of some patents which teach the use of proteases in cleaning compositions follows.
Jones et al, U.S. Pat. No. 3,790,482 teaches the use of a combination of an alkaline protease and an amylase in a dry granular laundry detergent composition. The composition of Jones et al includes an organic detergent, an alkaline builder salt, an alkaline protease, and an amylase and is generally used for laundering of fabrics.
Weber, U.S. Pat. No. 4,169,817 discloses a liquid cleaning composition containing a detergent builder, a surfactant, an alkaline protease, and an enzyme stabilizing agent which is a water soluble salt and/or a water soluble hydroxy alcohol. The composition of Weber may be used in a laundry presoak solution, as a laundry detergent, or may be used as a general purpose cleaner to clean processing equipment in the dairy and cheesemaking industries. The detergent solution of Weber generally has a pH in the range of 7.0 to 11.0.
Guilbert et al, U.S. Pat. No. 4,243,543 discloses a liquid detergent composition containing a protease which is stabilized by a stabilizing system which includes a reducing agent, a polyol, and a buffering agent. In one embodiment, Guilbert teaches a two-part cleaning composition for clean-in-place applications, in which a first part includes the enzyme, a detergent, and the stabilizing system; while a second, alkaline part includes a chelating agent. The pH of the use solution in this example of Guilbert is 11-12.
Although alkaline cleaning compositions which use preoteolytic enzymes have been proposed in the prior art for clean-in-place applications, the prior art compositions require relatively complicated enzyme stabilizing systems due to the number of additives in solution with the enzyme. Therefore, a simplified system in which the enzyme is storage stabilized without the expense and complexity of the prior art systems would be advantageous and economical as compared to the prior art.